Pawel Lejba, Space Research Center of the Polish Academy of Sciences; Tomasz Suchodolski, Polish Space Agency; Piotr Michalek, Space Research Center of the Polish Academy of Sciences
Keywords: laser ranging, space debris, orbit determination, space surveillance and tracking
Abstract:
After big modernization in 2014, the LASBOR station (CBK PAN Borowiec) has entered a new chapter of the laser measurements. With two independent Nd:YAG pulse laser modules, ie. the standard unit used for laser observations of all satellites equipped with retroreflectors (picosecond module EKSPLA PL-2250) and a high-energy module (nanosecond Continuum Surelite III) dedicated to Space Surveillance and Tracking (SST) activity, the station is able to track satellites (LEO and MEO), as well as space debris targets (LEO defunct satellites and rocket bodies). The tracking of typical rocket bodies has been launched in the middle of 2016. Today, the LASBOR station tracks over 100 different satellites (active/inactive) and rocket bodies. The defunct satellites are tracked in the frame of Space Debris Study Group (SDSG) of the International Laser Ranging Service (ILRS). The rocket bodies are tracked for the needs of Space Surveillance and Tracking (SST) programme. During last 3 years (2016-2019), the LASBOR station performed 1123 successfull passes of space debris objects, providing 13688 of normal points. An average RMS of these passes is on the level of 2 centimetres – 2 metres (depending on the laser module being used). Additionally, the LASBOR team calculated the orbits of several rocket bodies based on an one single laser track (in full rate measurements format), showing, that their covariance matrix can be improved approximately by 20-40 percent, even if the track has a time length of several dozen seconds. All orbital computations were performed by means of NASA Goddard’s GEODYN-II program in an Earth-Centered-Inertial True of Date reference frame. The input orbital elements of the targets were TLE files downloaded from the SPACETRACK database.
At Borowiec, a second independent laser-optical system is developed. This system is fully dedicated to the SST activity. The new system is situated on an azimuth-elevation mount with a 65 centimetres Cassegrain telescope equipped with servo drives that provide a tracking accuracy below 1 arcsecond, and a 8 inches RS guiding telescope equipped with two fast dedicated optical CMOS cameras. The whole system is controlled by a multiplatform steering/tracking software and support space debris/satellite predictions, real-time laser observations, system calibration, ADSB monitoring, data post-processing and other functions. The new sensor will be quipped with high-powerful laser module. The objective of this action is the tracking of uncooperative LEO targets with a diameter below 1 metre and participation in the building of the independent laser catalogue in a near future. Finally, the second sensor will operate 24 hours a day, 7 days a week. At present, this system is fully operational in optical mode.
Date of Conference: September 15-18, 2020
Track: Optical Systems & Instrumentation